1. Field of the Invention
The present invention relates to controlling a dynamic depth of stereo-view or multi-view images, and more particularly, to controlling a dynamic depth in order to obtain optimum parallax in stereo-view or a multi-view images for a comfortable dynamic view.
2. Description of the Related Art
Images, captured by a stereo-view or multi-view camera in a parallel form, are input to stereoscopic display devices, and such images are used for a stereoscopic display. Displacement of an object, that is a disparity, exists between stereo-view images formed of two predetermined visual points. Due to such a disparity, a viewer feels positive or negative parallax, and thus feels a dynamic depth. However, when a viewer views images having parallax for a long time, the viewer may be easily fatigued and may have side effects, such as nausea.
FIG. 1 is a diagram for describing a related art method of generating stable stereo-view images by horizontally moving each of the stereo-view or multi-view images left and right.
According to the related art method, in order to obtain an image suitable for a three-dimensional (3D) image display from a stereo-view or multi-view image, a disparity of a stereo-view image received at each frame is obtained using a related art disparity estimation method, and then a disparity histogram is obtained. The disparity histogram is moved in a negative direction based on a threshold, in order to suitably apply a ratio of positive disparity and negative disparity to each frame. The disparity histogram is moved by cropping both ends of the stereo-view image.
FIG. 2 illustrates diagrams of types of stereoscopic cameras. In a communication environment of a stereo-view image, a stable stereo-view image causing low fatigue can be obtained by employing various camera structures in a camera tube by regulating the disparity of a receiving terminal as illustrated in FIG. 2, like the one obtained by controlling a convergence angle of a stereoscopic camera.
A related art method and apparatus for controlling a dynamic depth were developed considering characteristics of a corresponding stereo-view image by using a disparity histogram. However, a threshold value for controlling a disparity was obtained experimentally based on a subjective evaluation, not based on an objective basis. Also, in order to produce a stable stereo-view image that does not cause fatigue, parallax should be inside a suitable range, but the related art method and apparatus do not consider such a range.
Moreover, in the case of sequence images captured using a stereo-view or multi-view camera, the sequence images need to be efficiently compressed due to the massive amount of data. Decoding the massive amount of data and then parity estimating restored images in order to provide comfortable dynamic depth to a viewer are inefficient and difficult to realize in a system.